A novel nonsense mutation of the KAL1 gene (p.Trp204*) in Kallmann syndrome

OBJECTIVE: To describe a novel KAL1 mutation in patients affected by Kallmann syndrome. SETTING: Endocrinology Clinic of the João de Barros Barreto University Hospital – Federal University of Pará, Brazil. METHODS: Clinical examination, hormone assays and sequencing of exons 5, 6 and 9 of the KAL1 gene in four Brazilian brothers with Kallmann syndrome. RESULTS: Detected a novel KAL1 mutation, c.612G.A/p.Trp204*, in four hemizygous brothers with Kallmann syndrome, and five heterozygous female family members. CONCLUSION: The novel p.Trp204* mutation of the KAL1 gene results in the production of a truncated anosmin-1 enzyme in patients with Kallmann syndrome. This finding broadens the spectrum of pathogenic mutations for this disease.